Tape drives are widely used for storing information in digital form. These tape drives commonly use a storage tape having a thin film of magnetic material which receives the information. Typically, the storage tape is moved between a pair of spaced apart reels, past a data transducer to record or read back information from the storage tape.
In one type of tape drive system, one of the reels is part of the tape drive while the other reel is part of a removable cartridge. For this type of tape drive system, the reel which is a part of the tape drive is commonly referred to as a take-up reel, while the reel which is a part of the cartridge is commonly referred to as a cartridge reel. With this system, upon insertion of the cartridge into the tape drive, it is necessary to couple the storage tape on the cartridge reel to the take-up reel of the tape drive. Subsequently, the storage tape must be uncoupled from the take-up reel, prior to removing the cartridge from the tape drive system.
Typically, a cartridge leader on the storage tape is automatically coupled to a take-up leader which is connected to the take-up reel during insertion of the cartridge into the tape drive. The procedure of connecting the take-up leader with the cartridge leader is commonly referred to as "buckling" or "coupling". Subsequently, during ejection of the cartridge, the cartridge leader is unbuckled from the take-up leader.
FIG. 1A illustrates a prior art cartridge leader 100 uncoupled from a prior art take-up leader 102. FIG. 1B illustrates the prior art cartridge leader 100 coupled to the prior art take-up leader 102. In this prior art embodiment, the cartridge leader 100 includes a hoop 104 and a notch 106, while the take-up leader 102 includes a mushroom shaped tab 108 having a nose 110 and a neck 112. The hoop 104 is dimensioned to enable the nose 110 and neck 112 of the take-up leader 102 to pass therethrough. The notch 106 is dimensioned to receive the neck 112, but prevent the nose 110 from passing therethrough. Commonly assigned U.S. Pat. Nos. 4,662,049 and 4,720,913 provide a detailed discussion of this type of tape buckling arrangements. The contents of U.S. Pat. Nos. 4,662,049 and 4,720,913 are incorporated herein by reference.
Unfortunately, this type of tape buckling arrangement is not completely satisfactory. Under certain circumstances, the take-up leader 102 can become unbuckled from the cartridge leader 100 before the cartridge leader 100 has been pulled onto the take-up reel. This is commonly referred to as "leader runaway". During leader runaway, the take-up leader 102 can retract onto the take-up reel and the cartridge leader 100 can retract into the cartridge.
One cause of leader runaway is a loss of tension in leaders 100, 102 before the cartridge leader 100 is pulled onto the take-up reel. During a loss of tension, the nose 110 can slip up into the hoop 104 and become disengaged from the notch 106. Another cause of leader runaway is excessive use of the tape drive. More specifically, the prior art leaders 100, 102 are each made of plastic. After excessive use, edges 114 of the nose 110 of the tab 108 begin to weaken. During usage, the weakened plastic edges 114 of the tab 108 can deflect and allow the tab 108 to pass through the notch 106.
When leader runaway occurs, the tape drive must be returned to the manufacturer for repairs and the customer does not have access to the information on the storage tape while the tape drive is being repaired. Accordingly, there is a need for an easy and accurate way to reliably couple and de-couple the storage tape to the take-up reel of tape drive.
In light of the above, it is an object of the present invention to provide a buckle for a tape drive and cartridge which securely retains the cartridge leader to the take-up leader. Another object of the present invention is to provide a buckle which resists unbuckling during a loss of tension in the leaders. Yet another object of the present invention is to provide a tape drive which is compatible with other prior art cartridges. Still another object of the present invention is to provide a buckle having improved durability, which is relatively easy and cost efficient to manufacture and utilize.